Heat-conductive adhesive sheet, manufacturing method for same, and electronic device using same

Abstract

The present invention provides a thermally conductive adhesive sheet that can be easily laminated on an electronic device without an adhesive layer therebetween and can further selectively dissipate heat in a particular direction to provide a sufficient temperature difference to the inside of the electronic device, a method for producing the same, and an electronic device using the same. The present invention includes a thermally conductive adhesive sheet comprising a high thermally conductive portion and a low thermally conductive portion, wherein the high thermally conductive portion and the low thermally conductive portion have adhesiveness, and the high thermally conductive portion and the low thermally conductive portion each independently constitute an entire thickness of the thermally conductive adhesive sheet, or at least either the high thermally conductive portion or the low thermally conductive portion constitutes a portion of a thickness of the thermally conductive adhesive sheet, and a method for producing the thermally conductive adhesive sheet, and an electronic device using the thermally conductive adhesive sheet.

The invention claimed is: 
     
       1. A thermally conductive adhesive sheet comprising a high thermally conductive portion and a low thermally conductive portion,
 wherein the high thermally conductive portion and the low thermally conductive portion have adhesiveness, and the high thermally conductive portion and the low thermally conductive portion each independently constitute an entire thickness of the thermally conductive adhesive sheet, or at least either the high thermally conductive portion or the low thermally conductive portion constitutes a portion of a thickness of the thermally conductive adhesive sheet, 
 wherein a thermal conductivity of the high thermally conductive portion is 0.5 (W/m·K) or more and 2000 (W/m·K) or less, and a thermal conductivity of the low thermally conductive portion is less than 0.5 (W/m·K), 
 wherein the high thermally conductive portion and the low thermally conductive portion are each formed of an adhesive resin composition, and 
 wherein the adhesive resin composition of the high thermally conductive portion comprises at least one of silica, alumina, magnesium oxide, a metal nitride, copper, and aluminum. 
 
     
     
       2. The thermally conductive adhesive sheet according to  claim 1 , wherein each adhesive resin composition comprises at least one of a thermosetting resin and an energy ray-curable resin. 
     
     
       3. The thermally conductive adhesive sheet according to  claim 2 , wherein each adhesive resin composition comprises at least said thermosetting resin and wherein the thermosetting resin is a silicone resin or a urethane resin. 
     
     
       4. The thermally conductive adhesive sheet according to  claim 1 , wherein the adhesive resin composition of the high thermally conductive portion comprises said metal nitride and said alumina. 
     
     
       5. The thermally conductive adhesive sheet according to  claim 4 , wherein the metal nitride is at least one of silicon nitride, aluminum nitride, magnesium nitride, and boron nitride. 
     
     
       6. The thermally conductive adhesive sheet according to  claim 4 , wherein the adhesive resin composition of the high thermally conductive portion comprises boron nitride and said alumina. 
     
     
       7. The thermally conductive adhesive sheet according to  claim 1 , wherein the thermal conductivity of the high thermally conductive portion of the thermally conductive adhesive sheet is 1.0 (W/m·K) or more and 2,000 (W/m·K) or less, and the thermal conductivity of the low thermally conductive portion is less than 0.5 (W/m·K). 
     
     
       8. An electronic device comprising the thermally conductive adhesive sheet according to  claim 1 . 
     
     
       9. A method for producing the thermally conductive adhesive sheet according to  claim 1 , comprising forming on a release sheet a high thermally conductive portion having a thermal conductivity of 0.5 (W/m·K) or more and 2000 (W/m·K) or less and formed of an adhesive resin composition and a low thermally conductive portion having a thermal conductivity less than 0.5 (W/m·K) and formed of an adhesive resin composition. 
     
     
       10. The thermally conductive adhesive sheet according to  claim 1 , wherein the thermal conductivity of the high thermally conductive portion is 1.0 (W/m·K) or more and 500 (W/m·K) or less, and the thermal conductivity of the low thermally conductive portion is 0.15 (W/m·K) or more and less than 0.5 (W/m·K). 
     
     
       11. The thermally conductive adhesive sheet according to  claim 1 , wherein the thermal conductivity of the high thermally conductive portion is 1.0 (W/m·K) or more and 500 (W/m·K) or less, and the thermal conductivity of the low thermally conductive portion is 0.15 (W/m·K) or more and 0.3 (W/m·K) or less. 
     
     
       12. The thermally conductive adhesive sheet according to  claim 1 , wherein the thermal conductivity of the high thermally conductive portion is 1.3 (W/m·K) or more and 500 (W/m·K) or less, and the thermal conductivity of the low thermally conductive portion is 0.15 (W/m·K) or more and 0.3 (W/m·K) or less. 
     
     
       13. The thermally conductive adhesive sheet according to  claim 1 , wherein the thermal conductivity of the high thermally conductive portion is 1.3 (W/m·K) or more and 500 (W/m·K) or less, and the thermal conductivity of the low thermally conductive portion is 0.15 (W/m·K) or more and 0.25 (W/m·K) or less. 
     
     
       14. The thermally conductive adhesive sheet according to  claim 1 , wherein at least either the high thermally conductive portion or the low thermally conductive portion constitutes a portion of a thickness of the thermally conductive adhesive sheet. 
     
     
       15. The thermally conductive adhesive sheet according to  claim 10 , wherein the high thermally conductive portion and the low thermally conductive portion each independently constitute an entire thickness of the thermally conductive adhesive sheet. 
     
     
       16. The thermally conductive adhesive sheet according to  claim 10 , wherein at least either the high thermally conductive portion or the low thermally conductive portion constitutes a portion of a thickness of the thermally conductive adhesive sheet. 
     
     
       17. The thermally conductive adhesive sheet according to  claim 1 , wherein the high thermally conductive portion and the low thermally conductive portion each independently constitute an entire thickness of the thermally conductive adhesive sheet, and wherein the thermal conductivity of the low thermally conductive portion is 0.15 (W/m·K) or more and less than 0.5 (W/m·K). 
     
     
       18. The thermally conductive adhesive sheet according to  claim 1 , wherein at least either the high thermally conductive portion or the low thermally conductive portion constitutes a portion of a thickness of the thermally conductive adhesive sheet, and wherein the thermal conductivity of the low thermally conductive portion is 0.15 (W/m·K) or more and less than 0.5 (W/m·K). 
     
     
       19. The thermally conductive adhesive sheet according to  claim 1 , wherein the adhesive resin composition of the high thermally conductive portion comprises at least one of said silica, said alumina, said magnesium oxide, and said metal nitride. 
     
     
       20. The thermally conductive adhesive sheet according to  claim 19 , wherein the metal nitride is at least one of silicon nitride, aluminum nitride, magnesium nitride, and boron nitride.